Methylation of APC tumor suppressor gene in bladder cancer

Bladder cancer is a major health problem in Egypt which constitutes 30% of all cancers. Cytology could serve as an excellent test for screening but it is of lower sensitivity. Early diagnosis is critical for maximizing the cure rate of bladder cancer , so many urine-based tumor markers have been developed for use in detecting and monitoring bladder cancers. Hypermethylation of CpG islands in the promoter regions of APC tumor suppressor gene is a major event in the origin of many cancers. In the present study detection of methylated APC gene was done in the urine of 183 subjects including normal, benign and malignant cases using MS-PCR technique. Results revealed marked urinary APC promoter hypermethylation in malignant group as compared to benign and normal groups. The sensitivity of detection of APC promoter hypermethylation was (57%) and the specificity was (98%), while the sensitivity of urine cytology was (44%).Combined use of detection of urinary APC promoter hypermethylation with urine cytology increased the sensitivity of cytology from 44% to 74%. So, detection of urinary APC promoter hypermethylation appears to be a promising marker for detecting new onset of bladder cancer.

Autorentext

Lecturer of medical biochemistry and molecular biology at Ain Shams faculty of Medicine.